Components are the central elements of any mapping design in MapForce. Generally, the term "component" is a convenient way to call any object which acts as a data source, or as a data target, or represents your data in the mapping at an intermediary processing stage.
There are two main categories of components: structure components and transformation components.
The structure components represent the abstract structure or schema of your data. For example, when you add an XML file to the mapping area (using the menu command Insert | XML Schema/File), it becomes a mapping component. For further information about structure components and their specifics, see Data Sources and Targets. With a few exceptions, structure components consist of items and sequences. An item is the lowest level mapping unit (for example, a single attribute in the XML file, or an element of simple type). A sequence is a collection of items.
The transformation components either transform data (for example, functions), or assist you in transformations (for example, constants or variables). For information on how you can use these components to achieve various data transformation tasks, see Designing Mappings.
With the help of structure components, you can either read data from files or other sources, write data to files or other sources, or store data at some intermediary stage in the mapping process (for example, in order to preview it). Consequently, structure components can be of the following types:
•Source. You declare a component as source by placing it on the left of the mapping area, and, thus, instructing MapForce to read data from it.
•Target. You declare a component as target by placing on the right of the mapping area, and, thus, instructing MapForce to write data to it.
•Pass-through. This is a special component type which acts both as a source and target (for further information, see Chained mappings / pass-through components).
On the mapping area, components appear as rectangles. The following sample mapping illustrates three source components, one target XML component, and various transformation components (functions and filters) through which data goes before being written to the source.
This mapping sample is available at the following path: <Documents>\Altova\MapForce2020\MapForceExamples\CompletePO.mfd.